What Is the Function of Bile?

Bile is digestive fluid made by the liver and stored in the gallbladder. It aids in digestion, absorption, excretion, hormone metabolism and other functions.

Bile juice is a digestive fluid produced by the liver. It is stored and concentrated in the gallbladder. Its main function is to convert fats in food into fatty acids, which are absorbed in the gut. Below are the important functions of bile.

Digestion

Bile is essential for the complete digestion of fats and, to some extent, of proteins and carbohydrates. This action is due to the presence of bile salts, which act in the following ways

• When digesting fats, bile acts as an emulsifier to break the large fat globules into smaller emulsion droplets. Emulsified fats provide a larger area for the fat-digesting enzymes (lipase) to act, making the process quicker.
• Bile acts as a good solvent. Due to this property, it serves as a good medium for the interaction of fats and fat-splitting enzymes.

Absorption

Bile helps in the absorption of various substances. This is also due to the presence of bile salts. The following things are absorbed with the help of bile

• Bile is essential for the absorption of fat, iron, calcium and vitamins. Bile salts help in the absorption of lipid-soluble vitamins A, D, E and K and the provitamin, beta carotene.

Excretion

Certain substances are excreted through bile, for instance

• Some metals, such as copper, zinc and mercury.
• Bile plays an important role in the removal of toxins from the body. Toxins from liver detoxification processes are secreted into bile and eliminated through feces (bowel function).
• Bile also serves as the route of excretion for bilirubin, a byproduct of red blood cell breakdown.
• Bile also carries excess cholesterol out of the body and dumps it into the gastrointestinal tract, where it can be passed out through the feces.

Laxative action

• Bile salts stimulate bowel movement (peristalsis).

Suitable pH

• Bile helps to maintain a suitable pH of the duodenal contents and thus, it helps the action of all enzymes. Bile is an important source of alkali for neutralizing the hydrochloric acid entering the intestine from the stomach.

Lecithin and cholesterol

Lecithin and cholesterol that are present in bile also help in some ways

• First, they are treated as food and are reabsorbed.
• Secondly, they act as adjuvants to bile salts in the process of emulsification of fats (but overall they are regarded as excreted products).

Lubricant

• Mucin of bile acts as a buffer and a lubricant.

Regurgitation of bile

• Regurgitation of bile in the stomach helps neutralize gastric acidity and thus, it prevents the injurious effect of acids on the gastric mucosa.

Hormonal function

• Bile salts function as "nutrient signaling hormones" by activating specific receptors. Bile salts also are presumed to collaborate with insulin to regulate the metabolism of nutrients in the liver.

The common signs and symptoms of bile duct cancer may include

• The first sign of bile duct cancer is the yellowish discoloration of the skin and eyes due to jaundice.
• A common symptom of bile duct cancer is abdominal pain. However, this appears only in the advanced stages and not in the early stages. Usually, the pain develops from the right side of the abdomen, just underneath the ribs. They may be associated with abdominal distention.
• People affected with bile duct cancer may have itching due to bile pigment accumulation.
• In patients with bile duct cancer, the stool is noticeably lighter in color or clay in color. This occurs due to obstruction to bile flow caused by the cancer cells.
• When bilirubin levels in the blood rise, it may also affect the color of urine, which may have a dark yellow appearance.
• Bile duct cancer patients complain of general muscle weakness or a decline in physical strength.
• There may be fever with or without shivering.
• There may be loss of appetite and weight.
• The person may report nausea with or without vomiting.